The ignition system of the cars in question consists of a distributor with a crankshaft rotation sensor, a coil, spark plugs, wires and an electronic switch. The ignition timing is controlled by the processor unit, which receives pulses from the crankshaft rotation sensor (sensor description see Ch. 4). Pulses are generated by a transducer based on an optical pair (LED photodiode) and shaper. The interruption of the LED emission is provided by a rotor with a slotted structure. Ignition moment pulses are formed by rotor slots located along the inner circumference, which determine the angular movement of the crankshaft (within 1 turn).